v4l2loopback

• https://github.com/umlaeute/v4l2loopback.git

v4l2tools

• https://github.com/mpromonet/v4l2tools

Install tools

• sudo apt install v4l-utils

How to enable videodev in sandbox?

• sudo apt-get install linux-generic
• reboot sandbox
• sudo modprobe videodev
• cd v4l2loopback
• sudo make
• sudo make install
• sudo depmod -a

Launch four virtual v4l2 interface devices (/dev/video0 ~ /dev/video3)

• sudo modprobe v4l2loopback devices=4

Build v4l2tools

• sudo apt-get install liblog4cpp5-dev libvpx-dev libx264-dev libx265-dev libjpeg-dev
• cd v4l2tools
• make

Build capture code for obtaining h264 frames

• g++ capture.c -o capture

input video to loopback

• sudo ffmpeg -re -i input.mp4 -map 0:v -f v4l2 /dev/video1

convert YU12 video to H264

• ./v4l2compress -f H264 /dev/video1 /dev/video0

check video format

• sudo v4l2-ctl --device /dev/video0 --all

run h264 frame capture

• ./capture -f -o

check frame is correct (should choose an I-frame)

• ffmpeg -loglevel trace -f h264 -i frame-73.raw frame-73.jpg